dry hop dilemma

Not an emergency, but looking for some advice...

I'm currently dry-hopping my latest brew (only my second attempt at dry hopping). It's in a 3-gallon glass carboy (1/2 batch) with 0.5 ounces each of Cascade (whole) and Amarillo (pellet). My plan was to dry-hop for 7 days (which would be this Thursday), rack to another carboy to let things settle/clear for a few days and then bottle this weekend. Problem is, I somehow forgot that I don't have a free 3-gallon carboy to rack into. This isn't so bad as I figured I would just skip the settling stage and rack from the dry-hop carboy to the bottling bucket. However, I can't bottle until sometime this weekend, which means that the beer will have to stay on the hops for 3 extra days than what I had planned. My other option is to rack into a larger, 6.5 gallon carboy until bottling day, but I am concerned with leaving too much headspace. Will dry hopping for 10 days (as opposed to 7 days) be OK? Or should I rack to the 6.5 gallon carboy?

Thanks!

Dry hopping for 10 days will be fine.

Well, the weekend came and went and the beer is still unbottled and on the dry hops. Any suggestions now? Should I move it into the 6.5 gallon?

leave it till the weekend. hop aroma and taste fades with time. if your really concerned you can rack to the 6.5 like you want. just fill the head space with CO2. if you have a keging system use the CO2 canister to fill the head space with gas. if you don't have that you can go get a small block of dry ice, do a yahoo local search to find a distributer. break it up into small pieces then put a few chunks in a glass of warm water. then as you are racking pour the fog and only the fog into the carboy. the fog is very high in CO2. you may need to add fresh chunks or more warm water to keep the fog going. be sure to get a fresh chunk and warm water just before you cap. flood the carboy with the fog and at the exact same time cap your carboy.

I guess I can leave it until the weekend - my concerns have to do with over extraction of tannins (?) and such. I had read that too long a dry hop can impart grassy and other off-flavors. But if it is just a matter of extracting more hoppy goodness, I can handle that!

Too long, as in months.

Just to follow-up...I finally bottled this beer after 17 days of dry-hopping. Sample tasted good. Will see how it is after a few weeks when the bottles are fully carbed.